How Common 4.10 Axle with Overdrive

I have been working on my father's 61 TR3A (TS68189LO) recently and it is fitted from the factory with 4.10 gears in the rear axle. My question is, how common was this ratio on overdrive equipped cars? I have heard tow tales. First, most all TR3A's and early TR4's came this way unless "Continental Gearing" was specified. Or, second, that this was an extremely rare option and few if any cars were so fitted (Bill Piggot is of this camp).

What is the consensus with other late TR3A's?

Until I got my grubby mitts on it, the axle had never been opened up much less removed from the chassis. Axle # TS66520 14/10. Has green/while paint swipe.

But I've also heard that they would build anything you wanted to pay for. So there is probably at least one that someone ordered without OD and with the 4.1. Having driven that way, tho, I would say its more of a racing configuration. Not really practical on the street.

In fact, my plan is to install 3.45 gears from one if the PI cars.

In reply to # 1477932 by charleyf
I am also thinking that most all of those "very few" that got the 4.1 axles were the cars with overdrive.
Charley

In fact, my plan is to install 3.45 gears from one if the PI cars.
Randall,
I have been using the 3.45 gears for a number of years now in both TR3&4. I do like them but they only give me a 300 to 400 RPM advantage. That seems to be a small advantage for the cost, unless one has to replace broken gears.
Charley